Water pollution because of toxic organic contaminants such as dyes, pesticides, hydrocarbons, antibiotics, etc. becomes a serious problem in a global scale today. Various technologies are developed for the treatment of contaminated water such as chemical precipitation, ion-exchange, adsorption, membrane filtration, coagulation-flocculation, floatation, electrochemical methods, and advanced oxidation are used in recent years.
Advanced oxidation
processes in presence of nanomaterials gained wide attention for the
remediation of contaminated water over the conventional methods because of its
low cost, less time consuming and simple in process. In this process, development of efficient semiconductor
based photocatalysts play a vital role. Among several nanomaterials, graphene
based nanomaterials are important for the enhancement of photocatalytic
activity of semiconductor nanostructures.
Due to the
unique properties of graphene it is used for remediation of contaminated water.
The graphene based nanomaterials offer several advantages due to their large
surface area and high electron content for the removal of organic species from
waste water. Graphene oxide (GO) is used due to its high oxygen contents, which
is responsible for the adsorption of metal ion in the GO sheets. The surfaces
of the hydrophobic materials can be functionalized to target the specific
contaminant via electrical and chemical interaction.
A composite
with GO and metal oxide have some useful features and used as effective
adsorbent in the waste water treatment. GO functionalised magnetic
nanomaterials are used for the rapid removal of tetracycline, oxytetracycline, dioxytetracline
organic pollutants. Reduced graphene oxide (rGO)/iron oxide composite has been
proved to be an excellent adsorber for the removal of 1-naphthylamine,
1-naphthol and naphthalene like compounds.
From the various
studies it is obvious that rGO-TiO2, single layer GO, TiO2-Graphene
sponge have higher tetracycline and ciprofloxacin adsorption capacity than any
other metal oxide based nanomaterials. GO-EDTA showed excellent Pd2+ adsorption capacity than any other adsorbant. Besides
metal removal graphene based material is also used for the removal of organic
pollutants by adsorption. In this way we can utilise the unique properties of graphene
and graphene based nanomaterials to minimize environmental pollution and health
hazards.
1. S. S. Boxi, S. Paria. Visible light induced enhanced
photocatalytic degradation of organic pollutants in aqueous media using Ag
doped hollow TiO2 nanospheres. RSC Adv 2015; 5, 37657-37668.
2. R. Levin, P.
Epstein, T. Ford, W. Harrington, E. Olson, E. Reichard, US drinking water
challenges in the 841 twenty-first century, Environmental
Health Perspectives 2002, 110, 43-52.
3. X. Qu, J.
Brame, Q. Li, P.J.J. Alvarez, Nanotechnology for a Safe and Sustainable Water
Supply: 846 Enabling Integrated Water Treatment and Reuse, Accounts of Chemical Research, 2012, 46, 834-843.
No comments:
Post a Comment